Sherif B. Mossad

The resurgence of swine-origin influenza A (H1N1).

Unexpectedly, swine-origin influenza A (H1N1) virus (S-OIV, informally known as swine flu) appeared in North America at the very end of the 2008–2009 influenza season and began to spread internationally. As the world mobilizes for a potential pandemic, this article summarizes the developments in diagnosis, treatment, and prevention. The health care system is mobilizing, while the world watches to see if this infection will become a pandemic or will just fade away, like the swine flu outbreak of 1976.

2008-2009 Influenza update: a better vaccine match.

Last year, the influenza vaccine did not match the circulating strains very well, and its overall protective efficacy was only 40%. All three antigens contained in the 2008-2009 vaccine are new. Surveillance data from the Southern Hemisphere during the summer of 2008 show that this vaccine is expected to match well the circulating strains in the Northern Hemisphere. Last flu season, some people may have lost their faith in flu shots. In the 2008–2009 flu season, we hope to do better.

Influenza in long-term care facilities: Preventable, detectable, treatable

Influenza in long-term care facilities is an ever more challenging problem. Vaccination of residents and health care workers is the most important preventive measure. Although vaccine efficacy has been questioned, the preponderance of data favors vaccination. Antiviral resistance complicates postexposure chemoprophylaxis and treatment. Factors that limit the choice of antiviral agents in this patient population include limited vaccine supplies and impaired dexterity and confusion in long-term care residents. Vaccination is the most important preventive measure. Early detection, infection control measures, prompt treatment, and preventive treatment of contacts can also help curtail an outbreak.

2012-2013 influenza update: hitting a rapidly moving target.

From the deadly 2009 influenza A H1N1 pandemic to the looming threat of bird flu H5N1, the recent outbreak of swine flu H3N2v at agriculture fairs, and the emergence of drug-resistant H1N1, we are constantly challenged by influenza viruses. Vaccination remains the main strategy for prevention. With the knowledge gained from past pandemics, an adequate vaccine supply, and an updated preventive strategy, we are in a better position to face the challenge. From the deadly 2009 H1N1 pandemic to the recent outbreak of swine flu H3N2v at county fairs, we are constantly challenged by influenza viruses.